Arrangement for and method of selectably changing the temperature of a product by employing a snap action invertible actuator

ABSTRACT

Axial pressure exerted against an invertible actuator breaks a membrane with a snap action and initiates a chemical reaction in which the temperature of a product in an inner container is changed.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to an arrangement that adds or removes heat from a product, such as a food, soup, beverage, medicine, or like product and, more particularly, to promoting user acceptance of the arrangement by enhancing its operation.

2. Description of the Related Art

Self-heating or self-cooling arrangements are known in which a product, typically a beverage, is heated or cooled by employing two chemical reactants which are stable when separated, but which produce an exothermic or an endothermic reaction when mixed. U.S. Pat. No. 4,793,323 shows one example of a single-use, self-heating container for liquids or solids, in which a breakable membrane keeps the reactants apart, and a breaking member is moved by a user to break the membrane and allow the reactants to mix to form the chemical reaction that changes the temperature of the product. Other examples of such single-use, self-heating containers that utilize breaking members can be found in my U.S. patent application Ser. No. 11/175,818, filed Jul. 6, 2005, and in my U.S. patent application Ser. No. 11/225,320, filed Sep. 13, 2005.

As advantageous as the known self-heating containers are, experience has shown that the actuation by the user is difficult for at least some users to perform. More specifically, the user is required to exert physical force to move the breaking member through a distance required to break the membrane and initiate the self-heating action. Some users, particularly the elderly and children, do not have the strength to activate the self-heating action.

SUMMARY OF THE INVENTION

1. Objects of the Invention

Accordingly, it is a general object of this invention to promote user acceptance, and to enhance the operation, of arrangements that add or remove heat from a product.

More particularly, it is an object of the present invention to eliminate a separate breaking member and to reduce the amount of physical force required to activate the temperature-changing action.

Still another object of the present invention is to provide a reliable arrangement for, and method of, selectably changing the temperature of a product.

2. Features of the Invention

In keeping with the above objects and others which will become apparent hereinafter, one feature of the present invention resides, briefly stated, in an arrangement for, and a method of, changing a temperature of a product, typically a food, soup or a beverage, comprising an outer container, preferably made of a thermally insulating material, having an upright axis and a side wall bounding an interior; and an inner container, e.g., a bowl or a cup, preferably made of a thermally conductive material, for example, a polyethylene coating over an aluminum core, fixedly mounted within the interior of the outer container and having a bottom wall bounding a chamber for containing the product. Preferably, the containers have juxtaposed flanges crimped together, or fused together by spin-welding, ultrasonic welding or high frequency welding.

In accordance with one feature of this invention, an actuator is invertible between stressed and unstressed positions, as described below. The actuator is preferably integrally formed with the side wall of the outer container, or the bottom wall of the inner container.

A breakable membrane, for example a circular, thin foil, is fixedly mounted on the actuator in the stressed position to bound a compartment therewith. A circular periphery of the membrane is adhered to an internal shoulder of the outer container. The membrane also bounds another compartment within the interior of the outer container. A pair of reactants is respectively contained in the compartments, and the reactants are kept apart by the membrane prior to use. For example, the reactants may be water and anhydrous calcium oxide or calcium chloride which, when mixed, produce an exothermic chemical reaction.

In accordance with this invention, the actuator is invertible upon exertion of axial pressure thereon by the user, and this axial pressure causes the actuator to invert from the stressed to the unstressed position with a snap action, and to break the membrane and allow the reactants to mix and produce the chemical reaction that changes the temperature of the product in the inner container.

In contrast to the known art, a separate breaking member is not mounted within the interior of the outer container in a juxtaposed relationship with the membrane. This simplifies assembly and cost, as well as the careful handling previously required to avoid injury due to pointed barbs on the breaking member. Moreover, the temperature changing action is not initiated by requiring expenditure of a significant amount of force by the user. Instead, the user need only lightly axially push on the actuator, which then seeks to self-return to its unstressed position with an abrupt, sudden force of a relatively large magnitude.

In the preferred embodiment, the actuator is a dome integrally formed, by molding or stamping, with one of the containers and has a so-called “natural” (i.e., unstressed) position with a certain curvature (e.g., concave) when removed from its forming tool, i.e., an injection mold or a stamping press. During assembly of the arrangement, the dome is pushed and inverted to a so-called “unnatural” (i.e., stressed) position with an opposite curvature (e.g., convex), thereby storing energy in the dome. One of the reactants is introduced into the dome in the stressed position, and the breakable membrane is then fixedly mounted over the dome in the stressed position to seal the one reactant therein. The dome maintains itself in the stressed position until the user lightly pushes on the actuator to initiate the self-heating action. Thereupon, the dome seeks to release the energy stored therein, and the self-return to the unstressed position occurs with a sudden, snap-action, and explosive force sufficient in magnitude to break the overlying membrane, again without the aid of any breaking member.

The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded view of one embodiment of an arrangement in accordance with this invention;

FIG. 2 is an enlarged, cutaway, perspective view of the arrangement of FIG. 1 after assembly;

FIG. 3 is a reduced scale, front elevational view of the arrangement of FIG. 1 after assembly;

FIG. 4 is a sectional view taken on line 4-4 of FIG. 3;

FIG. 5 is an enlarged sectional view taken on line 5-5 of FIG. 4;

FIG. 6 is an enlarged sectional view taken on line 6-6 of FIG. 4;

FIG. 7 is a broken-away sectional view of a portion of the container with the invertible actuator depicted in a stressed position;

FIG. 8 is a view analogous to FIG.7, but with the invertible actuator in an unstressed position;

FIG. 9 is a top plan view of a partially removed seal on a product cup for use in the arrangement of FIG. 1;

FIG. 10 is a top plan view of a sip lid for use in the arrangement of FIG. 1;

FIG. 11 is an exploded view of another embodiment of an arrangement in accordance with this invention;

FIG. 12 is an enlarged, front elevational view of the arrangement of FIG. 11 after assembly;

FIG. 13 is a sectional view taken on line 13-13 of FIG. 12;

FIG. 14 is a bottom perspective view of the inner container of FIG. 11 in the unstressed position;

FIG. 15 is a view analogous to FIG. 14, but in the stressed position;

FIG. 16 is a reduced scale, sectional view of the arrangement of FIG. 12 before actuation of a temperature change; and

FIG. 17 is a view analogous to FIG. 16, but after actuation of the temperature change.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As best shown in FIGS. 1-2, an arrangement in accordance with one embodiment of this invention includes an outer container 10 having a side wall 12 bounding an interior, and an inner container or cup 14 fixedly mounted within the interior of the outer container 10. An actuator 26 is integral with the side wall 12 and invertible, as described below, between a stressed position (FIG. 7) and an unstressed position (FIG. 8) within the interior of the outer container 10. A breakable membrane 16 is fixedly mounted within the interior of the outer container 10 to bound a compartment 18 with the cup 14, and the membrane 16 overlies the actuator 26 in the stressed position to bound another compartment 20 therewith. A pair of reactants 22, 24 (see FIG. 4) respectively contained in the compartments 18, 20 is kept apart by the membrane 16 prior to use, and the actuator 26 is operative for breaking the membrane 16, as described below, to allow the reactants 22, 24 to mix and form a chemical reaction that changes the temperature of a product contained in the cup 14. A seal 28 seals the product within the cup 14. An apertured sip lid 30 is optionally mounted over the seal 28 and over the outer container 10. An outer thermally insulating sleeve 44, preferably formed of corrugated board and pre-printed with product details, snugly surrounds the side wall 12 of the outer container. A plurality of integrally molded ribs 72 (see FIG. 1) at the exterior of the outer container ensures the snug fit and also adds an additional layer of air insulation. A protective base cap 46 is mounted at a lower end of the outer container to prevent accidental or non-accidental actuation of the actuator 26, and to support the arrangement on a planar support surface. The reactants and the product have been omitted from FIG. 2 so as not to obscure the interior of the arrangement.

The outer container 10 is symmetrical about an upright axis 32 (see FIG. 4), and the side wall 12 circumferentially surrounds the axis 32. The side wall 12 is preferably frusto-conical or cylindrical. As best seen in FIGS. 7-8, the outer container 10 is formed with an interior annular shoulder 34 on which a circular periphery of the membrane 16 is adhesively secured. The compartment 18 above the membrane 16 is filled with one of the reactants 22, for example, water, and the compartment 20 below the membrane 16 is filled with the other of the reactants 24, for example, anhydrous calcium oxide or calcium chloride. Other reactants are contemplated by this invention, and the positions of the reactants could be reversed, that is, the water could be in the lower compartment, while the anhydrous calcium oxide or calcium chloride could be in the upper compartment. The outer container 10 is preferably constituted of a thermally insulating moldable material, for example, a thermoformed foamed polypropylene, and the actuator 26 is molded integrally with the side wall 12 and is invertible, as described in detail below.

The inner cup 14 contains the product and is preferably constituted of a thermally conductive material, for example, a polyethylene coating over an aluminum core. Advantageously, a thin polyethylene film is laminated to a flat aluminum disk, and then the laminate is stamped into shape by a deep draw stamping process. The product can be virtually anything, but is preferably a beverage, such as coffee or tea, or a soup, or a foodstuff. In the case of a soup, the cup 14 can be shaped more as a bowl. The product can directly fill the cup/bowl 14, or in some cases, for example, in the case of a prepackaged soup, the product can be placed in a sealed pouch 50 (see FIG. 4), and the pouch then is placed in the cup/bowl.

The seal 28 seals the product within the cup. The seal 28, as best shown in FIGS. 1, 5 and 9, includes an annular rim 36 mechanically crimped over, or fused by spin-welding, ultrasonic welding, or high frequency welding with, a radial annular flange 38 of the cup 14, and a diaphragm 40 adhesively mounted on the rim 36 and peelably removable from the rim 36 by pulling on a pull tab 42. The rim, diaphragm and pull tab are preferably constituted of aluminum, which is stamped and die cut into their illustrated shapes. The seal 28 hermetically seals the product before and during the temperature change. Once the temperature change has been achieved, the pull tab is pulled to at least partially remove the diaphragm and gain access to the product.

The membrane 16 is a thin, tearable foil die cut into a circular shape and preferably constituted of aluminum. An adhesive at its periphery adheres the membrane to the shoulder 34 and is preferably thermally activated.

The outer container 10, as best seen in isolation in FIGS. 7-8, is an injection molded foamed polypropylene plastic and, as noted above, the shoulder 34 and the actuator 26 are of one-piece molded unitary construction therewith. The actuator 26 preferably has a dome shape and is connected to the annular shoulder 34 by a thinned, annular living hinge 52, which permits the actuator to be inverted between the stressed position of FIG. 7 and the unstressed position of FIG. 8. When the outer container is removed from its manufacturing injection mold, the dome 26 is in the unstressed (e.g., concave curvature) position, also sometimes referred to as the “natural” position of the dome. During assembly of the arrangement, the dome is affirmatively pushed and inverted to the stressed (e.g., convex curvature) position, also sometimes referred to as the “unnatural” position of the dome. During this inversion, the dome stores energy. Then, the dome, which maintains the stressed position, is filled with one of the reactants 24, and the breakable membrane is adhesively secured to the shoulder 34 in an overlying relationship with the dome to seal the reactant 24 in the compartment 20 therein. As shown in FIG. 7, the membrane 16 is intact.

If a light axial pressure is exerted by a user on a finger-receiving area 54 at the center of the dome 26 to initiate the self-heating action, then the center of the dome is pushed slightly inwardly into the container about the living hinge 52. The dome is constantly seeking to release the energy stored therein, and eventually a point is reached where the dome self-returns to the unstressed position with a sudden, snap-action, and explosive force sufficient in magnitude to break the overlying membrane 16. The reactant 22 in the upper compartment 18 flows downwardly through the ruptured membrane and chemically reacts with the reactant 24 in the lower compartment 20.

To promote the speed and efficiency of the chemical reaction, the user can shake the arrangement, typically for about 10-20 seconds, and can even invert the arrangement and allow it to stand, typically for less than two minutes. In the preferred embodiment, about 28 grams of a granulated calcium chloride (grain size 1-2 mm) are used. The liquid reactant need not be pure water, but can be glycerin. In about one minute's time, the temperature of the exothermic reaction (on the order of 200 degrees Centigrade) caused when water and calcium chloride interact raises the temperature of the product in the cup from a room temperature of about 19 degrees Centigrade to a temperature of about 60 degrees Centigrade, which is ideal for such products as soup or coffee.

Once the recommended waiting period has elapsed, the arrangement is returned to its original upright position, and the pull tab 42 is pulled back to either partially or completely remove the diaphragm 40 depending upon the type of product in the cup and how it will be consumed. For example, a spoon requires more room to access soup within the cup as compared to a beverage, which is directly sipped. If the soup pouch 50 is used, then the user first removes the lid 30; then the diaphragm 40 is peeled and opened; then the pouch is removed; then the contents of the pouch are poured into the cup, and then the lid 30 is snap-mounted back on the outer container. After the self-heating process has been completed, the lid 30 can once again be completely removed, or a small portion of the lid can be removed to provide access for a spoon. If the product is a beverage, such as coffee, then the sip lid 30 is snapped over the opened seal, and the beverage is consumed through an aperture 70 (see FIG. 10).

To prevent accidental or non-accidental actuation of the dome 26, the protective base cap 44 is mounted on a bottom flange 56 (see FIG. 6) at the lower end of the outer container. The cap includes a barrier wall 58 underlying and blocking access to the dome 26, an outer sleeve 60 surrounding the bottom flange 56, an upper flange 62 for capturing the bottom flange, and a pull tab 64 for enabling the base cap 44 to be removed by the authorized user. The absence of the base cap serves as visual evidence of tampering.

Turning now to the embodiment of FIGS. 11-17, an outer container 100 has a side wall 112 bounding an interior, and an inner container or bowl 114 has a bottom wall 115 and is fixedly mounted within the interior of the outer container. An actuator 126 is integral with the bottom wall 115 and invertible, analogously to the above description, between a stressed position (FIG. 16) and an unstressed position (FIG. 17) within the interior of the outer container. A breakable membrane 116 is fixedly mounted on, and underlies, the actuator 126 in the stressed position to bound a compartment 120 therewith, and also bounds another compartment 118 within the interior of the outer container 100. A pair of reactants 122, 124 (see FIG. 13) respectively contained in the compartments 118, 120 is kept apart by the membrane 116 prior to use, and the actuator 126 is operative for breaking the membrane 116, as described above, to allow the reactants to mix and form a chemical reaction that changes the temperature of a product contained in the bowl 114. A seal 128 seals the product within the bowl 114. A lid 130 having a liquid-tight opening 131 and a peelable foil 133 is optionally mounted over the seal 128 and over the outer container 100. An outer thermally insulating sleeve (not shown), analogous to sleeve 44, snugly surrounds the side wall 112 of the outer container 100. A formed ridge 135 on the exterior of the side wall 112 retains the insulating sleeve in its exterior position around the outer container.

Each container 100, 114 is symmetrical about an upright axis 132 (see FIG. 13). The inner container 114, as previously noted, is shaped as a bowl and is shorter in height and radially longer, as compared to the cup 14. The membrane 126 is adhesively secured at its outer annular peripheral edge to the bottom wall 115 of the bowl. As illustrated in FIG. 13, a powdered reactant, e.g., anhydrous calcium oxide or calcium chloride is in the compartment 120, while a liquid reactant, e.g., water, is in the compartment 118, although the positions of these reactants could be reversed. The outer container 100 is preferably constituted of a thermally insulating material, such as a thermoformed foamed polypropylene.

The bowl 114 contains the product and is preferably constituted of a thermally conductive material, for example, a polyethylene coating over an aluminum core. Preferably, a thin polyethylene film is laminated to a flat aluminum disk, and then the laminate is stamped into shape by a deep draw stamping process. The actuator 126 is formed integrally with the bottom wall 115 of the bowl by being stamped therefrom into a dome shape and is invertible, as described below.

As best seen in isolation in FIG. 14, when the bowl 114 is removed from its forming tool, the dome-shaped actuator 126 is in the unstressed or natural position in which it assumes a convex curvature. During assembly, the actuator is affirmatively pushed and inverted to the stressed or unnatural position depicted in FIG. 15 in which it assumes a concave curvature. As described above, energy is stored by the dome during this inversion. The dome maintains the stressed position while it is being filled with one of the reactants, and while the membrane 126 is adhesively secured thereto to seal the one reactant in the compartment 120.

In the case where the bowl 114 accommodates the soup-filled, prepackaged pouch 50, then the lid 130 and a peelable foil 137 on the seal 128 are first removed, and then the pouch 50 is removed from the bowl 114. Next, a light axial pressure is exerted by a user inside the bowl at a central interior area of the dome 126 to initiate the self-heating action. The center of the dome is pushed downwardly until a point is reached where the dome self-returns to the unstressed position with a sudden, snap-action and explosive force sufficient in magnitude to break the underlying membrane (see FIG. 17). The reactants mix and chemically react with one another. Next, the pouch is opened, and its contents poured into the bowl. The lid 130 is returned to its original position overlying the seal 128. The user then waits for the contents of the pouch to be heated and, to promote the speed and efficiency of the heating, the arrangement can be shaken and/or inverted. Once the heating period has elapsed, the liquid-tight opening 131 can be opened to provide access to the heated contents in the bowl. The opening 131 is made sufficiently large to allow a soup spoon to pass through without mechanical interference.

It will be understood that each of the elements described above, or two or more together, also may find a useful application in other types of constructions differing from the types described above.

While the invention has been illustrated and described as embodied in an arrangement for and method of selectably changing the temperature of a product by employing a dome-shaped actuator invertible by a snap action, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims. 

1. An arrangement for selectably changing a temperature of a product, comprising: a) an outer container having an upright axis and an interior; b) an actuator invertible between stressed and unstressed positions; c) an inner container mounted within the interior of the outer container and having a chamber for containing the product; d) a breakable membrane mounted on the actuator in the stressed position to bound a compartment therewith, and bounding another compartment within the interior of the outer container; e) a pair of reactants respectively contained in the compartments and kept apart by the membrane prior to use; and f) the actuator being invertible, upon exertion of axial pressure thereon, from the stressed to the unstressed position with a snap action to break the membrane and to allow the reactants to mix and form a chemical reaction that changes the temperature of the product in the inner container.
 2. The arrangement of claim 1, wherein the outer container is constituted of a thermally insulating material, and wherein the inner container is constituted of a thermally conductive material, and wherein the inner container is fixedly mounted to the outer container.
 3. The arrangement of claim 1, wherein the outer container has a side wall bounding the interior, and wherein the actuator is integral with the side wall of the outer container.
 4. The arrangement of claim 3, wherein the side wall is annular, wherein the container has an internal annular shoulder, and wherein the membrane is a foil having an annular periphery adhered to the shoulder.
 5. The arrangement of claim 1, wherein the inner container has a bottom wall, and wherein the actuator is integral with the bottom wall of the inner container.
 6. The arrangement of claim 1, wherein the actuator has a dome shape having opposite curvatures in the stressed and unstressed positions.
 7. The arrangement of claim 6, wherein one of the containers and the actuator are formed by a forming tool, and wherein the actuator has a dome shape with an initial curvature upon removal from the tool, and wherein the actuator has a curvature identical to the initial curvature in the unstressed position.
 8. The arrangement of claim 1, wherein the reactants are water and anhydrous calcium oxide or calcium chloride.
 9. The arrangement of claim 1, wherein the inner container has a flange; and a seal for sealing the inner container, the seal including an annular rim mechanically crimped over the flange of the inner container, and a peelable diaphragm detachably mounted on the rim, the diaphragm having a pull tab for enabling the diaphragm to be at least partly peeled from the rim.
 10. The arrangement of claim 1, and an apertured lid mounted with snap action over the containers.
 11. The arrangement of claim 1, wherein the outer container has a plurality of outer ribs, and a thermally insulating sleeve mounted on the ribs exteriorly of the outer container.
 12. The arrangement of claim 1, wherein the outer container has a bottom flange, and a tamper-resistant cap removably mounted on the bottom flange, the cap having a barrier wall for preventing access to the actuator until the cap is removed.
 13. The arrangement of claim 1, wherein the product is contained in a pouch, and wherein the pouch is received in the inner container; and wherein the inner container has a bowl shape.
 14. A method of selectably changing a temperature of a product, comprising the steps of: a) at least partly filling an inner container with the product; b) sealing the product within the inner container; c) fixedly mounting the sealed, product-filled inner container inside an outer container having an upright axis and an interior; d) forming an actuator of one-piece construction with one of the containers, the actuator being invertible between stressed and unstressed positions; e) mounting a breakable membrane on the actuator in the stressed position to bound a compartment therewith, and to bound another compartment within the interior of the outer container; f) at least partly filling a pair of reactants respectively into the compartments; and g) inverting the actuator, by exerting an axial pressure thereon, from the stressed position to the unstressed position with a snap action to break the membrane and to allow the reactants to mix and form a chemical reaction that changes the temperature of the product in the inner container.
 15. The method of claim 14, wherein the forming step is performed by forming the actuator as a dome having opposite curvatures in the stressed and unstressed positions.
 16. The method of claim 14, wherein the forming step is performed by a forming tool by forming the actuator with a dome shape having an initial curvature upon removal from the tool, and wherein the actuator has a curvature identical to the initial curvature in the unstressed position.
 17. The method of claim 14, wherein the forming step is performed by integrally forming the actuator with the outer container, wherein the sealing step is performed by mounting a seal on the inner container, and wherein the inverting step is performed by exerting the axial pressure inwardly toward the seal.
 18. The method of claim 14, wherein the forming step is performed by integrally forming the actuator with the inner container, and wherein the inverting step is performed by exerting the axial pressure from inside the inner container.
 19. A method of making an arrangement for selectably changing a temperature of a product, comprising the steps of: a) at least partly filling an inner container with the product; b) sealing the product within the inner container; c) fixedly mounting the sealed, product-filled inner container inside an outer container having an upright axis and an interior; d) forming an actuator of one-piece construction with one of the containers with an unstressed curvature; e) inverting the actuator to a stressed curvature opposite to the unstressed curvature; f) mounting a breakable membrane on the actuator with the stressed curvature to bound a compartment therewith, and to bound another compartment within the interior of the outer container; and g) at least partly filling a pair of reactants respectively into the compartments.
 20. The method of claim 19, and the step of removably mounting a tamper-resistant cap on the outer container, for preventing access to the actuator until the cap is removed.
 21. The method of claim 19, and wherein the forming step is performed by integrally molding the actuator with a side wall of the outer container.
 22. The method of claim 19, and wherein the forming step is performed by integrally stamping the actuator from a bottom wall of the inner container.
 23. A bowl-shaped container for receiving a product whose temperature is to be changed, the container comprising: a) a bottom wall; b) a dome-shaped actuator of one-piece construction with, and integrally formed from, the bottom wall, the actuator being invertible between a concave curvature above the bottom wall and a convex curvature below the bottom wall.
 24. The container of claim 23, and a breakable membrane mounted on the concavely curved actuator to bound therewith a compartment to be filled with a reactant. 